Field of Invention
The present invention relates to a radiation dose detector, and more particularly to an embedded optical fiber radiation dose detector.
Description of Related Arts
Due to changes in environmental factors in modern society, the number of people worldwide suffering from cancer is rising, and radiotherapy, as an effective method for treating cancer, has been heavily used in medical community. In the course of radiotherapy, a lot of radiations such as α-ray, γ-ray and X-ray are applied to the tumor from different directions, which are able to damage the DNA of tumor cells to inhibit the growth and proliferation. However, if the patients receive too much radiation during radiotherapy, it will cause great harm to physical health organizations.
Conventionally, in the course of radiotherapy, due to lack of precise location and radiation dose control, too much damage is caused to surrounding healthy tissue by radiation. Thus, optimized effect of radiotherapy is to provide an optimal dose of radiation to a designated target area, while allowing the adjacent surrounding healthy tissues receive minimized radiation dose, which requires real-time monitoring tumor moving, and real-time detecting radiation dose and accumulated dose at tumor and surrounding healthy tissues thereof at a radiation area.
According to the paper “Radiation Therapy Physical quality control and quality assurance” (Deng Xiaowu, China Cancer 2008 Vol. 17 No. 8, page 660-665), since the 21st century, radiotherapy has developed to three-dimensional conformal radiotherapy, intensity modulated conformal radiotherapy and image guided radiation therapy stages, so as to provide millimeter-level target positioning and dynamic four-dimensional planing dose distribution computing. Even so, the conventional radiation dose control is still using indirect methods such as vitro measurements and phantom calibration (paper: “For patients with IMRT plan dosimetry verification” by Dai Jianrong, Hu Yimin, Zhang Chi, Guan Ying, Zhang Wang Chuang, Chinese Journal of Radiation Oncology, September 2004, Vol. 13 No. 3 page 229-233). Direct in-vivo measurements and in-vivo reusable position calibration methods are absent.
Conventionally, it is impossible to satisfy requirements for real-time monitoring radiation absorbed dose, because almost all standard sensors for detecting the radiation absorbed dose are too large, material safety thereof is insufficient, life time thereof is short, etc. In recent years, western countries began to study X-ray sensors whose X-ray fluorescent material is applied on a optical fiber surface where cladding is removed, which is able to detect radiation dose (Dan Sporea, Laura Mihai, Ion Tiseanu, Multidisciplinary evaluation of X-ray optical fiber sensors, Sensors and Actuators A, 213: 79-88, 2014). However, a proportion of fluorescent signal coupling into an optical fiber core with such technology is low, and sensitivity thereof is poor. Furthermore, such technology needs a large probe, which is difficult for in-vivo radiation dose measurement.
In view of the above shortcomings, present invention is finally obtained after a long period of study and practice.